Mule Palm Lesion Mimic Mutants (LMM)

[LeonardHolmes]

The latest issue of Palms has a fascinating article on "Suspected Lesion Mimic Mutants in Mule Palms."  It seems that 20-30% of mule palms probably carry a gene combination that causes the older leaves to whither and die in the sun.  The leaves look like they have a nutrient deficiency or a disease, but it is likely just in their genes.  I bought some seedlings from Mule Palms of Mississippi a while back and some slightly larger ones from another source.  I have been noticing that the leaves on a few of them look like they have issues.  Now I'm guessing that they just have the LMM genetic problem.  Have others noticed this?

[Allen]

possibly regarding article and the leaves toward bottom with small spotting- potassium deficiency is magnified in the sun - fertilizer always cleared mine up in full sun.  In winter they can't uptake the nutrients and revert

[Tomas]

Have something very similar on my mule palm. The most obvious explanation would be potassium deficiency, but I feed this plant with a lot of sulpomag (Patentkali here in Europe) with no result

[LeonardHolmes]

2 hours ago, Allen said:

possibly regarding article and the leaves toward bottom with small spotting- potassium deficiency is magnified in the sun - fertilizer always cleared mine up in full sun.  In winter they can't uptake the nutrients and revert

It does look like that.  All of mine got Osmocote w/ Minors (which has been renamed).  If the article is right then 20-30% of all mule palms will have a genetic defect that causes these symptoms and does not respond to any nutrients or fungicide.  

[LeonardHolmes]

1 minute ago, Tomas said:

Have something very similar on my mule palm. The most obvious explanation would be potassium deficiency, but I feed this plant with a lot of sulpomag (Patentkali here in Europe) with no result

That looks like the LMM as described in the article. If they are right there is no cure.

 

[Chester B]

I've had 6 mules and have not seen this on any of them.   It looks like what I see on my Kentia palms - those things are never happy.

[Allen]

2 hours ago, Tomas said:

Have something very similar on my mule palm. The most obvious explanation would be potassium deficiency, but I feed this plant with a lot of sulpomag (Patentkali here in Europe) with no result

Cooler/wet temps can do this to these palms as well

[Tomas]

1 hour ago, Allen said:

Cooler/wet temps can do this to these palms as well

The last winter was the warmest I have ever experienced and we are just coming out of a hot and dry summer 

[Allen]

2 hours ago, Tomas said:

The last winter was the warmest I have ever experienced and we are just coming out of a hot and dry summer 

Do the fronds grown since May look like the pics you shared?  Or are the pics from fronds that endured winter?  I am looking at your weather history for Rome and there are multiple days in 30's F or at or just above 0 C.  Mule palms while cold hardy doesn't mean that the fronds can take frost/snow and not take some damage which shows worse when temps warm

https://www.wunderground.com/history/monthly/it/ciampino/LIRA/date/2024-1

 

[LeonardHolmes]

13 hours ago, Allen said:

Do the fronds grown since May look like the pics you shared?  Or are the pics from fronds that endured winter?  I am looking at your weather history for Rome and there are multiple days in 30's F or at or just above 0 C.  Mule palms while cold hardy doesn't mean that the fronds can take frost/snow and not take some damage which shows worse when temps warm

 

You have a beautiful mule palm, Allen - and you do a great job of protecting it in zone 7b.  You seem skeptical of the University of Florida study that was based on studying hundreds of mule palms.  They have found, based on studying multiple commercial growers, that 20-30% of mule palms may carry a genetic flaw - probably related to their nature as an inter species hybrid.  

I'm happy that you got a good one, but I'm not sure you can explain away their finding based on your experience.  

[Allen]

42 minutes ago, LeonardHolmes said:

You have a beautiful mule palm, Allen - and you do a great job of protecting it in zone 7b.  You seem skeptical of the University of Florida study that was based on studying hundreds of mule palms.  They have found, based on studying multiple commercial growers, that 20-30% of mule palms may carry a genetic flaw - probably related to their nature as an inter species hybrid.  

I'm happy that you got a good one, but I'm not sure you can explain away their finding based on your experience.  

No I am skeptical that @Tomas ' s   photos are your genetic mutation in the report as opposed to cold damage that occurs on my palm every year and looks like his pics.  I don't want you making every one that has mule palm damage think it is this genetic thing.  Here is mine after cold damage..........

[LeonardHolmes]

That makes sense.   @Tomas ' s lesions also look a lot like the LMM lesions.   I found the article oddly reassuring.  If I have 10 seedlings then I can expect to throw away 2 or 3 of them when the mutation becomes evident.  It may also be reassuring to others who have tried nutrients, fungicides, and other treatments to no avail.  In some cases the solution will be to replace the palm.  The odds are in your favor that the next one won't have the mutation. 

[Jeff zone 8 N.C.]

Has anyone tried a foliar feed to try to cure this?

[Tomas]

19 hours ago, Allen said:

Do the fronds grown since May look like the pics you shared?  Or are the pics from fronds that endured winter?  I am looking at your weather history for Rome and there are multiple days in 30's F or at or just above 0 C.  Mule palms while cold hardy doesn't mean that the fronds can take frost/snow and not take some damage which shows worse when temps warm

https://www.wunderground.com/history/monthly/it/ciampino/LIRA/date/2024-1

 

Actualy the palm grows not in Rome, but in my garden at Santa Marinella and  the appropriate place for looking at the temperatures would be Civitavecchia

It is not freezing there since 2018 and the palm probably have never seen temperatures lower than 0°C/32F. The new fronds are green, also those coming out of the last winter, than the symptoms (of whatever it is - I actualy hope it is not the genetical problem as it should be lethal as stated in the article) get more visible as the leaves age. I noted the symptoms two - three years ago and the problem is getting more serious with time. Before there were no symptoms. I will take a picture of the whole plant later

To me it doesn't look like cold damage, but it would be helpfull if people that grow mules could state that their plant shows similar damage/different damage/ no damage at around 32F

 

 

[Tomas]

Here is a picture from May 2023, the plant looks quite green